best poker for testing your adaptability?

everyone swears by texas hold'em but honestly i feel like you can just play tight and not think much. omaha throws me off way more because of all the possibilities, but i always second guess if that's just because i don't play it as much. stud games feel weird too, since you have to remember a bunch of dead cards and adjust. i started dabbling in mixed games but it's hard to tell if that's actually making me better or just frying my brain. curious if anyone else thinks one variant actually forces you to adapt or if it all blends together after a while.